Dave Grohl and the Foo Fighters have been touring the country for their HBO music doc Sonic Highways, and for each episode, viewers are treated to a visual and audio labor of love as the band tours different cities in search of a historic place to record. Along the way, they sit down with various musicians from those cities and explore the past. It’s been a hell of a ride, but it was just this past week that they explored Seattle, the epicenter of grunge. For Grohl, the city is his “phantom limb”, as he can always feel it even when he’s not present.

Of course, the city has become synonymous for many with the name Nirvana, and it was expected that Grohl would delve into his thoughts on Kurt Cobain, who died in 1994 of a self-inflicted gunshot wound. The result was an emotional journey into the past, where Grohl remembers playing the Foo Fighters’ first demo tapes for Cobain and getting his complete approval.

“Kurt heard that, and kissed me on the face, as he was in a bath. He was so excited. He was like, ‘I heard you recorded some stuff with Barrett [Jones].’ I was like, ‘Yeah.’ He was like, ‘Let me hear it.’ I was too afraid to be in the same room as he listened to it,” he said.

Grohl also spoke to his peers about Cobain, including Death Cab For Cutie frontman Ben Gibbard, who said that Cobain’s death hit him hard as a teen.

“It’s this weird thing that happens with musicians where they get intertwined in your life. I never met this dude, but his loss…it was like losing a friend. It sounds so cliché to say that, but as a kid — and I’d never met this person in my life — it was really devastating. Even as you’re feeling it, you’re like, “Why am I reacting this way? He’s just a guy who played guitar.” But he wasn’t just a guy who played guitar. It’s probably what people my parents’ age felt like when John Lennon was killed. This person you think is always going to be there and who you’re looking for to musically make sense of things in life. When they leave, it’s devastating. People don’t feel that way about other entertainers,” he told Rolling Stone.

Cobain is the subject of a new documentary, the first ever to have the complete cooperation and backing of his family. Kurt Cobain: Montage of Heck will be executive-produced by his daughter, Frances Bean.